Picture of Doug Ross

Doug Ross

Technical Services Manager Martin's Brand

Post Date
Tuesday - May 22 - 2018
Post Title

Pesky Lawn Moths Are Destroying Your Lawn

Pesky Lawn Moths Are Destroying Your Lawn?

Sod Webworm Larva

On warm, humid evenings, you may see pale-brown moths with prominent “snouts” flying in a jerky zigzag pattern over the grass as you stroll through your lawn. These are the adult (moth) stage of sod webworms. The larvae, or caterpillars live in and feed on the grass, and can cause major damage to your lawn, especially during periods of drought.


Sod Webworm Pupa

Sod webworm caterpillars overwinter in lawns and begin feeding again in the spring. In late May through early June they make their cocoons (pupate), and adult moths emerge about 2 weeks later. After mating, each female moth can lay up to 200 eggs in the lawn. New caterpillars hatch in 7 – 10 days and feed on the grass through early August. These larvae then pupate and produce a second generation of moths. Caterpillars from eggs laid by the second wave of adult moths continue to feed on the grass through late September.


Sod Webworm Damage

Sod webworm chew off leaves and stems just above the crown. This feeding often causes brown patches up to the size of a baseball in the lawn. Sometimes these patches have pencil-sized holes in them where birds have looked for the caterpillars. The most severe damage usually occurs in July and August. As webworm larvae continue to grow and feed, the injured areas enlarge and coalesce into larger brown patches. This damage can easily go unnoticed during periods of drought. Fine fescue, Kentucky bluegrass, and other grass species are susceptible to webworm feeding.

Sod Webworm Upclose Damage


Cyonara® Lawn & Garden
Insect Control Concentrate

Cyonara Lawn & Garden Ready-to-Use Spray

Martins® has several products to control sod webworms. Cyonara® Lawn & Garden Insect Control is a concentrate that you dilute in water and spray on your lawn. Calculate the area (square footage) of the lawn to be treated by multiplying the length by the width. Then follow the mixing directions in the table for “Lawns” on the label.


Cyonara® Lawn & Garden
Ready-to-Use Spray

Cyonara Lawn & Garden Ready-to-Use Spray

Cyonara L & G Ready-to Spray is a ready-to-use version of Cyonara L & G Insect Control. It’s packaged in a hose-end sprayer, so no measuring and mixing is needed. After shaking the product well, connect the Ready-to-Spray nozzle to a hose and follow the application directions on the label. One quart of Cyonara L & G Ready-to Spray will cover 16,000 square feet (slightly more than ⅓ of an acre).


FLEE® Ready-to-Use Yard Spray

FLEE Ready-to-Use Yard Spray

FLEE® Ready-to-Use Yard Spray is another product that controls sod webworms, as well as fleas, ticks and mosquitoes. It’s another ready-to-use formulation and is applied similarly to Cyonara L & G Ready-to Spray.
For best webworm control using any of these products, completely wet the grass a few hours before applying the product, and don’t water or mow the grass for 24 hours after treatment.